get the python version from env

[DavidChan0519]

Motivation

The Python setup.py is using the fixed py_limited_api: py39, which will cause confusion when I use Python 3.10 to package the Python wheel.

Modifications

get the Python version from environment, do not use the fixed py39

Checklist

• Format your code according to the Code Formatting with Pre-Commit.
• [x ] Add unit tests as outlined in the Running Unit Tests.
• Update documentation / docstrings / example tutorials as needed, according to Writing Documentation.
• Provide throughput / latency benchmark results and accuracy evaluation results as needed, according to Benchmark and Profiling and Accuracy Results.
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[DavidChan0519]

@ispobock help review it please, thanks!

[DavidChan0519]

@BBuf help review it please, thanks!

[BBuf]

@BBuf help review it please, thanks!

@zhyncs I am not familar this，please have a look，thanks！

[FlamingoPg]

I think we dont need to add env for setup.py, py_limited_api is the minimum Python version that our project can accept.
@DavidChan0519 @BBuf @merrymercy @zhyncs

[FlamingoPg]

Reference

Adapt from https://scikit-build-core.readthedocs.io/en/latest/guide/build.html#binary-wheels-and-distributing
A wheel filename has several components:

scikit_build_core-0.1.2-py3-none-any.whl
|_______________| |___| |_| |__| |_|
         |          |    |    |    \
       name      version |    |  platform
                      python  |
                             abi

The three new items here (compared to SDists) are the compatibility tags:

python tag: The first version of Python the wheel is compatible with. Often py3 for pure Python wheels, or py312 (etc) for compiled wheels.

abi tag: The interpreter ABI this was built for. none for pure Python wheels or compiled wheels that don’t use the Python API, abi3 for stable ABI / limited API wheels, and cp312 (etc) for normal compiled wheels.

platform tag: This is the platform the wheel is valid on, such as any, linux_x86_64, or manylinux_2_17_x86_64.

Examples:

And the py_limited_api is for abi tag, For example:

sgl_kernel-0.0.5.post3-cp39-abi3-linux_x86_64.whl

cp39 means we build from cp39, and abi3 means stable for higher python version.

[zhyncs]

This makes nonsense to me. We don't need this at all. @DavidChan0519 @merrymercy